Alan, your advice is probably good. One can never be too safe.

But when I wrap the sandpaper around the (roughly) 3/8" dia. piece of foam and insert it, it immediately folds over in a controlled and predictable manner and sand the inside without any excitement, exactly like sanding the outside of a piece. I have never had even the slightest hint that it could catch. I suppose that if the inside was really really rough and had big chunks and slivers facing forward or if I forcefully jammed the hemostat in that it could catch. I think that the biggest risk might be if a person jammed the hemostat into a very small opening that the hemostat could get stuck in the opening. I think that is the real risk. But I may be working with a 2" opening and a hemostat width of maybe 3/4 inch or less.

When I'm sanding the interior I might start with 60 or 80 grit and stop around 150 or 220. It is a fast process. Also, I don't spend very much time sanding deeper than a person's finger can go.